The acquisition of expression of hTERT, the catalytic subunit of the telomerase enzyme, seems to be an essential step in the development of a majority of human tumors. However, little is known about the mechanisms preventing telomerase gene expression in normal and transformed cells that do not express hTERT. Using a methylation-specific PCR-based assay, we have found that the CpG island associ...

Genistein, the most abundant isoflavone present in soybean has antiproliferative effects on a variety of cancer cells, including prostate cancer. However, the molecular mechanism of antiproliferative effects of genistein is not entirely understood. Because the activation of telomerase is crucial for cells to gain immortality and proliferation ability, we examined the role of genistein in the re...

Telomerase is crucial for human carcinogenesis. The limiting component of telomerase activity is telomerase reverse transcriptase (hTERT), undetectable in differentiated somatic cells but present in most tumor cells. There is evidence that hTERT transcription is shut down by a repressor in normal cells, but the mechanisms that turn on or maintain expression in tumor cells are not understood. To...

MCPH1, a repressor of human telomerase reverse transcriptase (hTERT) function, is implicated in cellular immortalization. But little is known about how MCPH1 represses telomerase activity. In this study, to determine the mechanism by which MCPH1 regulates hTERT gene expression, we examined the role of MCPH1 in regulating the hTERT promoter in vitro. Co-transfection of the hTERT promoter with MC...

Reconstitution of telomerase activity by ectopic expression of telomerase reverse transcriptase (hTERT) results in an immortal phenotype in various types of normal human cells, including fibroblasts. Despite lack of transformation characteristics, it is unclear whether hTERT-immortalized cells are physiologically and biochemically the same as their normal counterparts. Here, we compared the gen...

Telomerase activity has a close relationship with malignancies in many cell types and it is tightly regulated at the transcriptional level of human telomerase reverse transcriptase (hTERT). Utilizing the hTERT promoter, the authors developed a gene delivery system of Fas associated protein with death domain (FADD) (hTERT/FADD). FADD is a protein which plays an important role in the apoptotic pa...

Activation of the telomere maintenance mechanism is a key hallmark of cancer. Human telomerase reverse transcriptase (hTERT) is the catalytic subunit of telomerase, which is highly expressed in more than 80% of tumors, including hepatocellular carcinoma (HCC). However, the exact mechanisms by which hTERT is up-regulated in HCCs and promotes tumor growth and progression is not fully understood. ...

BACKGROUND One of the major components of telomerase is the human telomerase reverse transcriptase (hTERT) as the catalytic protein. hTERT mRNA expression are reported to be associated with prognosis and tumor progression in several sarcomas. However, there is no clear understanding of the mechanisms of hTERT in human sarcomas. Recent studies have suggested that signals transmitted through p38 ...

Because the apoptotic pathway is often disrupted in tumor cells, its genetic restoration is a very attractive approach for the treatment of tumors. To treat malignant gliomas with this approach, it would be preferred to restrict induction of apoptosis to tumor cells by establishing a tumor-specific expression system. Telomerase is an attractive target because the vast majority of malignant glio...

The human telomerase reverse transcriptase (hTERT) is the catalytic subunit of the telomerase holoenzyme. Evidence is accumulating to link hTERT to activities other than telomere maintenance and immortalization. Here, we show that hTERT overexpression not only reduces the basal cellular reactive oxygen species (ROS) levels but also inhibits endogenous ROS production in response to stimuli that ...